Deb Gustafson, speaks as Ware Elementary School at Fort Riley, Kansas., as the school was rededicated in memory of Maj. Gen. Keith L. Ware, who was killed in Vietnam. (Photo by Mollie Miller/ U.S. Army)

Army Maj. Gen. Keith L. Ware was surveying a Vietnamese battlefield in a helicopter to get a better sense for his infantry division’s offensive when he came under enemy fire. The aircraft crashed in a fiery wreck seven miles from the Cambodian border, military officials said later that day, and all eight men on board were killed.

The Sept. 13, 1968, incident robbed the U.S. Army of one of its most respected general officers at the time. Ware first joined the Army as a draftee in 1941, and was awarded the Medal of Honor, the nation’s top decoration for combat valor, for leading his battalion on Dec. 26, 1944, through a fierce battle near Sigolsheim, France. As a lieutenant colonel, he went 150 yards ahead of the front elements of his unit, eventually leading a small patrol forward to capture four enemy machine-gun positions and kill numerous German riflemen.

Ware, 52 at the time of his death, is among the last U.S. general officers killed in a combat zone before Tuesday. The latest occurred when a man dressed as an Afghan soldier opened fire on a group of coalition troops at the Marshal Fahim National Defense University, a training academy for Afghan soldiers on the western outskirts of Kabul, coalition military officials said. The attack killed Maj. Gen. Harold J. Greene, deputy commanding general of Combined Security Transition Command-Afghanistan in Kabul. He is believed to be the highest-ranking officer killed in a combat zone since the Vietnam War.

A look at U.S. generals killed in some previous conflicts:

Nearly a dozen general officers and one admiral were killed while supporting military operations in Vietnam. They include Maj. Gen. George William Casey Sr., whose helicopter went missing over Vietnam on July 7, 1970. It was found four days later with the remains of the general and six other service members. The general’s son, George Casey Jr., later became a four-star general and retired as the Army chief of staff in 2011.

Some of the others include Rear Adm. Rembrandt C. Robinson, who died in a helicopter crash in the Gulf of Tonkin on May 8, 1972 and Army Brig. Gen. William R. Bond, who earned a Silver Star for valor during World War II and became the only U.S. general officer killed by ground fire in Vietnam on April 1, 1970, according to the Military Times Hall of Valor. He was hit with a gunshot round to the chest, according to an Associated Press news account at the time.

Korean War
At least one senior officer, Army Lt. Gen. Walton H. Walker, was killed in Korea. He died Dec. 22, 1950, on his way to Seoul in a vehicle accident while trying to pass a stalled convoy of South Korean military vehicles, according to Arlington National Cemetery. He was said to be a protege of Gen. George S. Patton, and earned a Distinguished Service Cross, the Army’s second-highest award for valor, for leading his soldiers during World War II in an offensive in France near the Seine River on Aug. 23, 1944, according to his award citation.

World War II
Dozens of U.S. generals and admirals were killed in action in World War II, when large-scale naval engagements and heavy ground fighting were both common.

Among the most famous is Navy Rear Adm. Daniel J. Callaghan, who was on board the USS San Francisco on Nov. 12-13, 1942, when it engaged in the campaign to take the Pacific island of Guadalacanal from Japanese troops. He was killed when his ship was bombarded, and was posthumously awarded the Medal of Honor for “ingenious tactical skill and superb coordination of the units under his command.” Callaghan’s naval forces defeated a larger Japanese foe “against tremendous odds,” according to his award citation.

Army Lt. Gen. Leslie J. McNair’s death also has been closely studied. He was killed July 25, 1944, in France during the Battle of Normandy by a U.S. bomber in an infamous friendly fire incident. He was posthumously promoted to four-star general, according to the Army.

Another senior officer famously killed in World War II was Army Lt. Gen. Simon Bolivar Buckner Jr. He was mortally wounded by artillery fire during the Battle of Okinawa in Japan on June 18, 1945, according to the Dwight D. Eisenhower Presidential Library, where some of his papers are kept. It occurred while he was commanding the 10th Army, which included both Army and Marine Corps units, according to the website Together We Served. He was posthumously promoted to four-star general.